In particular, the primary implement can be the main cutting unit of the combine harvester. So, for instance, it can be a grain or a maize cutting unit. In particular, the secondary implement can be a mowing unit, a cutting unit, or a swathing unit.
The secondary implement is arranged further to the rear of the header of the combine harvester than the primary implement. This means that during normal working in the forward travel of the combine harvester, first the primary implement fulfils its function, and after further movement the secondary implement fulfils its function. In normal operation, the movement of the secondary implement is arranged such that it moves parallel to the ground. This ensures an even processing of the ground.
In the case that impediments—e.g. deep ground undulations, trenches, rocks, etc.—must be crossed, the whole header, including the two implements, is lifted. However, if the header is one that is used for the so-called “high-cut” operation, there is the problem that, although the primary implement has been lifted up sufficiently high to pass over the impediment, the secondary implement, which is much closer to the ground, is too low for this. Thus, there is the danger of damage to the secondary implement when passing over the impediment.
A similar problem emerges during road transport of the header when it is dismounted from the combine harvester. When the header is separated from the combine harvester and loaded onto a trailer for road transport, then both implements attached to the harvester must be lifted over the wheels of the trailer. In the above described arrangement of displacement in the vertical direction of the two implements, the problem arises that, although the primary implement is arranged above the wheels, the secondary implement will still collide with them.